Renovating your house to include a second bathroom means more than just convenience; it means a more valuable home, too. Adding a bathroom can be a big undertaking, though, and you'll need the help of a few professionals. Still, it's a good idea to estimate your costs and budget before getting started.
Decide where the new bathroom will be. Unless you're willing to add a whole new addition to the house to have your extra bathroom, the new room will be formed from the existing square footage.
Measure your space and draw up scaled plans. If you're adding a full bathroom, you'll need room for a tub, toilet and sink. If you have enough space, consider installing a whirlpool or garden tub, as this will add even more value. If space is tight, consider just a toilet and sink for a half bathroom, or a walk-in shower to make it a "three-quarters bath."
Call local contractors to get estimates. You'll need a plumber to install the piping and drains and an electrician to run the power. If you want to do most of the renovation yourself you can cut down on labor costs.
Pick out fixtures you like, including a toilet, sink and bath tub/shower enclosure. You can get ideas online or you can go down to your local home improvement store. Write down prices so you can compare them later. Remember to include other necessities: sink fixtures, lighting, a pedestal or cabinet with countertop for the sink, painting supplies, a mirror or medicine cabinet, towel racks, a toilet paper holder, a faucet and shower head for the shower, switch plates and outlet covers and a door for privacy. Price flooring (according to the square footage) and lumber, insulation and drywall for making walls for the new room.
Add up the prices for the fixtures and accessories you have chosen. Add this to the professional installation of plumbing and electricity and you'll have an approximation of what your project will cost you.
If you need to demolish any existing walls, ask the plumber and electrician to check the walls to ensure there are no pipes or wires running through them. Keep safety in mind at all times.
If your area requires you to pull a permit, make sure to get that done before you start, and have the proper inspections. Don't risk getting fined or having to rip out everything you just did because it wasn't up to code. Pulling a permit usually only costs a couple hundred dollars, if that, depending on the area. Don't forget to add this cost to your calculations.